Estimating energy service demand and CO2 emissions in the Chinese service sector at provincial level up to 2030

China has been through a rapid development process of expanding tertiary industries and urbanization. Due to the aggressive expansion of service building space, energy consumption and CO2 emissions from the service sector are increasing significantly. In this study, we concentrate on China's service sector and analyze CO2 emissions from six sub-sectors: offices, mercantile, food and lodging, education, healthcare and others. Considering the gap of tertiary industry development status and climate diversity across regions, we base our study on regional analyses and the study subjects include 31 provincial regions of mainland China. We first estimate floor area and energy service demand of each sub-sector based on difference-influencing indicators. Then we conduct a scenario analysis and use an AIM/Enduse bottom-up cost optimization model to evaluate the CO2 reduction potential brought about by efficient technologies in China's service buildings. The results show that: 1) office and mercantile are two major sub-sectors in the service sector, while most of the floor area increase in the service sector is due to office buildings; 2) by 2030 a considerable part of energy consumption will be replaced by renewable energy, which leads to no-regrets CO2 emissions reductions; 3) renewable energy penetration potential is smaller in regions with larger tertiary industry GDP and CO2 emission reductions in cold and warm regions are caused by consumption decrease of coal and electricity respectively; 4) the optimization analysis allocates more reduction potential to regions with a smaller tertiary GDP share.